PSI Woodworking CUG3418CC Utility Grip 4 Jaw Lathe Chuck System Heavy duty chrome-plated self-centering chuck will hold your work tight & secure on midi and full size woodworking lathes Chuck is pre-threaded to 1" x 8tpi. Includes 3/4" x 16tpi adaptor Includes #1 Step Jaws 3/32" to 1-7/8" External & 11/32" to 3-3/8" Internal. Includes #2 Round Jaws 1-1/2" to 3-1/8" External & 2" to 3-7/8" Internal Includes Screw Chuck. Also includes an Allen Wrench and a set of Tightening Levers This C series chuck works with all "C" series jaws